<script lang="ts" setup name="XtxCarousel">
import { bannerList } from '@/types/data'
import { setInterval } from 'timers/promises';
import { onBeforeUnmount, onMounted, ref } from 'vue';
// import { PropType } from 'vue'
//vue3的父传子接受的方式 没有类型校验
// defineProps({
//   slides:{
//     type:Array,
//     required:true
//   }
// })
//有类型校验 需要配合protype 比较麻烦
// defineProps({
//   slides: {
//     type: Array as PropType<bannerList>
//   }
// })
interface props {
  slides: bannerList[]
  StartIndex?: number
  autoplay?: boolean
  duration?: number
  isShowInd?: boolean
}
// vue3+ts 方便快捷
const { slides, StartIndex = 1, autoplay = false, duration = 1000, isShowInd = false } = defineProps<props>()
const activeindex = ref(StartIndex)
const pre = () => {
  activeindex.value--
  if (activeindex.value < 0) {
    activeindex.value = slides.length - 1
  }
}
const next = () => {
  activeindex.value++
  if (activeindex.value >= slides.length) {
    activeindex.value = 0
  }
}
let timerid: number = -1
onMounted(() => {
  // if (!autoplay) return
  start()
  // 在ts中，使用定时器，window.setInterval
  // timerid = window.setInterval(() => {
  //   next()
  // }, 1000);
})

onBeforeUnmount(() => {
  clearInterval(timerid)
  // stop()
})
const stop = () => {
  clearInterval(timerid)
}
const start = () => {
  if (!autoplay) return
  //优化代码
  clearInterval(timerid)
  timerid = window.setInterval(() => {
    next()
  }, duration);
}
</script>

<template>
  <div class="xtx-carousel" @mouseenter="stop" @mouseleave="start">
    <ul class="carousel-body">
      <li class="carousel-item " :class="{ fade: activeindex === index }" v-for="(item, index) in slides"
        :key="item.id">
        <RouterLink to="/">
          <img :src="item.imgUrl" alt="" />
        </RouterLink>
      </li>

    </ul>
    <a href="javascript:;" class="carousel-btn prev" @click="pre"><i class="iconfont icon-angle-left"></i></a>
    <a href="javascript:;" class="carousel-btn next" @click="next"><i class="iconfont icon-angle-right"></i></a>
    <div class="carousel-indicator">
      <span @mouseenter="activeindex = index" :class="{ active: activeindex === index }" v-for="(item, index) in slides"
        :key="item.id" v-if="isShowInd"></span>
    </div>
  </div>
</template>

<style scoped lang="less">
.xtx-carousel {
  width: 100%;
  height: 100%;
  min-width: 300px;
  min-height: 150px;
  position: relative;

  .carousel {
    &-body {
      width: 100%;
      height: 100%;
    }

    &-item {
      width: 100%;
      height: 100%;
      position: absolute;
      left: 0;
      top: 0;
      opacity: 0;
      transition: opacity 0.5s linear;

      &.fade {
        opacity: 1;
        z-index: 1;
      }

      img {
        width: 100%;
        height: 100%;
      }
    }

    &-indicator {
      position: absolute;
      left: 0;
      bottom: 20px;
      z-index: 2;
      width: 100%;
      text-align: center;

      span {
        display: inline-block;
        width: 12px;
        height: 12px;
        background: rgba(0, 0, 0, 0.2);
        border-radius: 50%;
        cursor: pointer;

        ~span {
          margin-left: 12px;
        }

        &.active {
          background: #fff;
        }
      }
    }

    &-btn {
      width: 44px;
      height: 44px;
      background: rgba(0, 0, 0, 0.2);
      color: #fff;
      border-radius: 50%;
      position: absolute;
      top: 228px;
      z-index: 2;
      text-align: center;
      line-height: 44px;
      opacity: 0;
      transition: all 0.5s;

      &.prev {
        left: 20px;
      }

      &.next {
        right: 20px;
      }
    }
  }

  &:hover {
    .carousel-btn {
      opacity: 1;
    }
  }
}
</style>